The present invention relates to a method of manufacturing an opening leaf upper module intended to be mounted at the periphery of a glass panel of a vehicle, and to an opening leaf upper module of this type comprising in particular a rigid frame and a flexible weather strip. The invention applies in particular to an opening leaf for the sliding side window glass panel of a motor vehicle although it may just as easily be applied to other types of opening leaf such as those used in the fields of aeronautical, rail or naval engineering.
As is known, opening leaf modules, particularly for motor vehicles, consist of a heterogeneous collection of a great many parts with different functions, sizes and materials, thus requiring a great many operations to manufacture and assemble these modules. Motor vehicle side door opening leaf modules can be broken down into two sub-modules which are separated from one another by the line known as the waistline of the bodywork which can typically be seen running approximately along the horizontal glass panel wiping lips and which comprise two opening leaf modules, the upper and lower modules respectively.
With regard to the opening leaf upper module, this generally comprises a rigid door frame, usually made of metal, on which there is mounted a flexible strip that weatherproofs and guides the moving glass panel and is made of an elastomeric material that may or may not have a reinforcing member. A door frame of this type may, for example, be produced by assembling pressed sheet, metal section pieces that have been extruded and deformed by mechanical action (e.g. by bending, curving or hydroforming) or alternatively of injection-molded or cast metal components. These frames in particular have the disadvantage of being manufactured independently of the corresponding sealing/guiding strips, which means that a relatively high number of operations need to be performed in order to manufacture the corresponding upper modules, thus leading to a build-up of dimensional spread on the end-product.
Document GB-A-2 272 469 introduces an opening leaf upper module for a motor vehicle side door, the rigid frame of which is not made of metal but is molded in a thermoplastic material, and the rubber weather strip and guide of which is secured to this frame by overmolding of the molded frame previously coated with an adhesion promoter that encourages the rubber of the strip to stick, in an injection molding machine that vulcanizes this rubber following this overmolding.
One major disadvantage with the manufacturing method described in that document lies in the need to perform two successive steps: molding the frame and overmolding with vulcanization, thus leading to a relatively high cost of manufacture. Another disadvantage with this method lies in the need to use an adhesion promoter to encourage the strip to stick to the frame.